Quality assessment of Tsurang River water affected by coal mining along the Tsurangkong Range, Nagaland, India

Abstract

Tsurang, a major river in the Mokokchung district of Nagaland, northeast India, shares great aspects of traditional importance for the Ao Naga tribes and is a part of natural commodity providing water to the agrarian community for irrigation and livestock rearing. However, various environment detrimental activities are practiced along the course of the riverbank, particularly coal mining and agriculture. The present study was conducted to examine the seasonal water quality index (WQI) of the Tsurang river from three selected sampling stations. Overall, the water quality status was rated as “Good” in winter and spring while “Poor” in summer and autumn. In all the seasons, downstream (S3) located at the human settlement area presented higher WQI values compared to upstream (S1) and midstream (S2). The parameters such as turbidity, DO and BOD played a central role in affecting the WQI; although, no such significant roles in case of nutrient elements were observed in affecting the water quality. The WQI revealed that Tsurang river water is deteriorated due to coal mining and other anthropogenic activities practiced along the stretch of the river and the water needs to be pretreated before consumption. Therefore, proper management strategies and conservation efforts should be enforced and regulated by policymakers to protect the river from further contamination.